As described in Patent Literature 1, an absorbent body with a desired shape is formed in such a way that, a pulp sheet is crushed by a crusher including a plurality of rotating blades into fluff pulp, a mixed flow is formed by carrying the fluff pulp on an air flow to a duct and at the same time supplying a water absorbing polymer in the duct to be merged with the fluff pulp carrying flow, and the mixed flow is then transported to a rotating fiber stacking drum so that the mixed flow is adsorbed and retained by an adsorbent molding section which is formed on the outer circumference of the rotating fiber stacking drum.